Pilot/Controller Glossary
5/19/22
a.
The Minimum Safe Altitude (MSA) specified
in 14 CFR Part 91 for various aircraft operations.
b.
Altitudes depicted on approach charts or
departure procedure (DP) graphic charts which
provide at least 1,000 feet of obstacle clearance for
emergency use. These altitudes will be identified as
Minimum Safe Altitudes or Emergency Safe
Altitudes and are established as follows:
1.
Minimum Safe Altitude (MSA). Altitudes
depicted on approach charts or on a DP graphic chart
which provide at least 1,000 feet of obstacle clearance
within a 25
−
mile radius of the navigation facility,
waypoint, or airport reference point upon which the
MSA is predicated. MSAs are for emergency use only
and do not necessarily assure acceptable navigational
signal coverage.
(See ICAO term Minimum Sector Altitude.)
2.
Emergency Safe Altitude (ESA). Altitudes
depicted on approach charts which provide at least
1,000 feet of obstacle clearance in nonmountainous
areas and 2,000 feet of obstacle clearance in
designated mountainous areas within a 100-mile
radius of the navigation facility or waypoint used as
the ESA center. These altitudes are normally used
only in military procedures and are identified on
published procedures as “Emergency Safe
Altitudes.”
MINIMUM SAFE ALTITUDE WARNING
(MSAW)
−
A function of the EAS and STARS
computer that aids the controller by alerting him/her
when a tracked Mode C equipped aircraft is below or
is predicted by the computer to go below a
predetermined minimum safe altitude.
(Refer to AIM.)
MINIMUM SECTOR ALTITUDE [ICAO]
−
The
lowest altitude which may be used under emergency
conditions which will provide a minimum clearance
of 300 m (1,000 feet) above all obstacles located in
an area contained within a sector of a circle of 46 km
(25 NM) radius centered on a radio aid to navigation.
MINIMUMS
−
Weather condition requirements
established for a particular operation or type of
operation; e.g., IFR takeoff or landing, alternate
airport for IFR flight plans, VFR flight, etc.
(See IFR CONDITIONS.)
(See IFR TAKEOFF MINIMUMS AND
DEPARTURE PROCEDURES.)
(See LANDING MINIMUMS.)
(See VFR CONDITIONS.)
(Refer to 14 CFR Part 91.)
(Refer to AIM.)
MINIMUM VECTORING ALTITUDE (MVA)
−
The lowest MSL altitude at which an IFR aircraft will
be vectored by a radar controller, except as otherwise
authorized for radar approaches, departures, and
missed approaches. The altitude meets IFR obstacle
clearance criteria. It may be lower than the published
MEA along an airway or J-route segment. It may be
utilized for radar vectoring only upon the controller’s
determination that an adequate radar return is being
received from the aircraft being controlled. Charts
depicting minimum vectoring altitudes are normally
available only to the controllers and not to pilots.
(Refer to AIM.)
MINUTES-IN-TRAIL
−
A specified interval be-
tween aircraft expressed in time. This method would
more likely be utilized regardless of altitude.
MIS
−
(See METEOROLOGICAL IMPACT
STATEMENT.)
MISSED APPROACH
−
a.
A maneuver conducted by a pilot when an
instrument approach cannot be completed to a
landing. The route of flight and altitude are shown on
instrument approach procedure charts. A pilot
executing a missed approach prior to the Missed
Approach Point (MAP) must continue along the final
approach to the MAP.
b.
A term used by the pilot to inform ATC that
he/she is executing the missed approach.
c.
At locations where ATC radar service is
provided, the pilot should conform to radar vectors
when provided by ATC in lieu of the published
missed approach procedure.
(See MISSED APPROACH POINT.)
(Refer to AIM.)
MISSED APPROACH POINT (MAP)
−
A point
prescribed in each instrument approach procedure at
PCG M
−
4